title: Genetic Mapping and Chromosomal Assignment of Magnaporthe oryzae Avirulence Genes AvrPik, AvrPiz, and AvrPiz-t Controlling Cultivar Specificity on Rice.
abstract: ABSTRACT A genetic map including three avirulence (Avr) genes, AvrPik, AvrPiz, and AvrPiz-t, was constructed in a genetic cross of two rice field isolates, 84R-62B and Y93-245c-2. The chromosomal locations of the Avr genes were determined by using selected markers to probe Southern blots of the parental chromosomes that had been separated by contour-clamped homogenous electric fields electrophoresis. Electrophoretic karyotyping showed that both parental isolates 84R-62B and Y93-245c-2 contained seven chromosomes greater than 3.5 megabases (Mb) in size and 84R-62B possessed a small chromosome of approximately 1.6 Mb. The linkage groups containing AvrPiz and AvrPiz-t were assigned to chromosomes 3 and 7, respectively. Some markers from the linkage group that contained AvrPik hybridized with chromosome 1 and the 1.6-Mb chromosome, yet all of the cloned RAPD markers that were closely linked to AvrPik hybridized exclusively to the 1.6-Mb chromosome in 84R-62B, the parent that possesses AvrPik. Thus, we conclude that AvrPik is located on the 1.6-Mb chromosome in 84R-62B.
authors.forename: Chao-Xi
authors.initials: CX
authors.lastname: Luo
authors.forename: Liang-Fen
authors.initials: LF
authors.lastname: Yin
authors.forename: Satomi
authors.initials: S
authors.lastname: Koyanagi
authors.forename: Mark L
authors.initials: ML
authors.lastname: Farman
authors.forename: Motoaki
authors.initials: M
authors.lastname: Kusaba
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yaegashi